In 2015, the Internet Engineering Task Force (IETF) released Protocol HTTP/2,the second major version of the Hypertext Transfer Protocol (HTTP), designed to optimize web performance and improve the speed and efficiency of web data exchanges. While maintaining the foundational principles of its predecessor, HTTP/1.1, this new version introduces key technical advancements, making browsing faster and smoother. This article explores the main innovations of HTTP/2 in enhancing web performance

Multiplexing in HTTP/2: Sending Multiple Requests Simultaneously for Better Performance

One of the primary limitations of HTTP/1.1 was its handling of requests: each request had to wait for the previous one to complete, creating a blocking effect. HTTP/2 addresses this issue through multiplexing, which allows multiple requests and responses to be sent simultaneously over a single TCP connection. This improvement is especially beneficial for modern, content-rich websites. By eliminating queue delays, multiplexing significantly reduces page load times, allowing content to display faster.

Header Compression in HTTP/2: Less Redundancy, More Speed

In HTTP/1.1, headers—often repetitive, like cookies—added to the data load, slowing down exchanges. HTTP/2 introduces header compression to minimize this redundancy. By compressing redundant data, HTTP/2 reduces the amount of data transmitted and optimizes response times. This feature is particularly advantageous for applications and websites that frequently exchange large amounts of data.

Persistent Connections: Boosting Web Efficiency and Performance

HTTP/2 uses a single persistent TCP connection, limiting the overhead associated with setting up a connection for each request. This persistent connection supports multiple exchanges and reduces resource consumption, avoiding delays associated with establishing new connections. Paired with Transport Layer Security (TLS), this approach enhances security while improving overall performance.

Request Prioritization in HTTP/2: Boosting Performance by Loading Essentials First

Another innovative feature of HTTP/2 is the ability to prioritize certain requests. Prioritization ensures that essential elements of a page, such as CSS and JavaScript, load before less critical components. This improves the user experience by giving priority to layout and structural elements, creating the perception of faster load times.

Limitation of HTTP/2: The Need for HTTPS

Despite its many benefits, HTTP/2 does come with an important constraint: most modern browsers require HTTPS to enable HTTP/2. This requirement strengthens the security of exchanges while allowing full use of the protocol’s enhancements, thanks to the advantages of TLS.

Conclusion

HTTP/2 represents a significant evolution in the HTTP protocol, meeting the increasing performance demands of the modern web. Innovations like multiplexing, header compression, and request prioritization improve data exchanges, making browsing faster and smoother. However, to leverage these improvements, HTTPS activation remains a prerequisite for most browsers, providing an additional layer of security and an enhanced user experience.